A design scheme of water quality monitoring sensor node based on wireless sensor networks is presented.The node consists of sensor module

main processor module

wireless communication module and power supply module.The sensor module which is connected to the main processor by RS-485 bus uses separate sensor module structure.The main processor and the wireless communication modules are designed based on CC2430 chip which is consistent with the IEEE802.15.4 protocol.Several sensor nodes make up networks use Zig Bee stack protocal automatically to build up an automatic water quality monitoring system with flexible set up of parameters and rapid deployment of nodes.